1-D TIRE APPARATUS

• US 20110140581A1
• Filed: 08/29/2008
• Published: 06/16/2011
• Est. Priority Date: 08/29/2008
• Status: Active Grant

• Current Assignee: Compagnie générale des établissements Michelin
• Original Assignee: Michelin Recherche et Technique SA (Compagnie Generale DES Etablissements Michelin SCA)
• Inventors: Christenbury, Damon L., Weston, David A.
• Granted Patent: US 8,476,808 B2
• Time in Patent Office: Days
• US Class Current: 310/365
• CPC Class Codes: B29D 2030/0072 Attaching fasteners to tyres, e.g. patches, in order to connect devices to tyres
• CPC Class Codes: B60C 19/00 Tyre parts or constructions not otherwise provided for
• CPC Class Codes: B60C 2019/004 Tyre sensors other than for detecting tyre pressure
• CPC Class Codes: B60C 23/0411 Piezoelectric generators
• CPC Class Codes: B60C 23/0493 for attachment on the tyre
• CPC Class Codes: G01M 17/02 Tyres
• CPC Class Codes: H10N 30/03 Assembling devices that include piezoelectric or electrostrictive parts
• CPC Class Codes: H10N 30/302 Sensors
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49538 Tire making
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 428/24479 including variation in thickness

Abstract

Disclosed is a tire mountable apparatus and methodology for mounting devices within a tire. In certain embodiments a signal generator may be mounted to the tire to generate signals based on changes in the radius of curvature of a tire. A piezoelectric sandwich and/or a substrate is/are provided having a length and width based at least in part on tire dimensions and positioned in the tire such that the longer length dimension is positioned laterally with respect to the width of the tire. The sandwich and/or substrate is/are sized such that the width dimension provides substantially no response to changes in the circumferential radius of curvature of the tire so that the length dimension defines the primary bending direction while the width dimension provides a strain free mount for associated devices.

Claims

1. A tire mountable apparatus, comprising:

a substrate having a first surface and a second surface; and

a pair of terminal/support elements extending from said first surface,

wherein said first surface has length L and width W, wherein L>

2W, and W<

the length of arc subtended along the inner surface of a tire corresponding to 5°

of rotation measured from a line extending from the center of rotation to the inner surface of an unloaded tire inflated at rated pressure, and

wherein said pair of terminals extends from said first surface in a line 90°

±

10 °

to a line in the direction of the length L, and the line 90°

±

10°

to the direction of length L identifies the direction of rotation of a supporting tire.

2. The tire mountable apparatus of claim 1, wherein said pair of terminals extends from said first surface in a line 90°

±

5°

to a line in the direction of the length L, and the line 90°

±

5°

to the direction of length L identifies the direction of rotation of a supporting tire,

4. The tire mountable apparatus of claim 1, further comprising:

an elastomeric patch having a first surface and a second surface separated by a mesa,

wherein said second surface of said substrate is adhered to said first surface of said elastomeric patch.

5. The tire mountable apparatus of claim 4, wherein said mesa has a height H, wherein 0<

H≦

5 mm, and wherein L>

W>

H.

6. The tire mountable apparatus of claim 4, further comprising:

a layer of piezoelectric material having a top surface and a bottom surface;

a first conductive layer covering said top surface; and

a second conductive layer covering said bottom surface;

wherein said piezoelectric layer, said first and second conductive layers, and said substrate form a sandwich structure, and wherein said sandwich structure is secured to the first surface of said elastomeric substrate.

7. The tire mountable apparatus of claim 4, wherein the substrate is FR4.

8. The tire mountable apparatus of claim 6, wherein the piezoelectric material is lead zirconium titanate (PZT).

10. The tire mountable apparatus of claim 6, wherein a first terminal/support element of the pair of terminal/support elements is electrically coupled to the first conductive layer and a second terminal/support element of the pair of terminal/support elements is electrically coupled to the second conductive layer.

11. The tire mountable apparatus of claim 6, wherein said sandwich structure is secured to said upper surface of said elastomeric substrate with an adhesive.

13. The tire mountable apparatus of claim 1, wherein said pair of terminal/support elements are spaced apart a distance less than about 18 mm.

14. The tire mountable apparatus of claim 1, wherein the width W is less than about 30 mm.

15. The tire mountable apparatus of claim 1, further comprising a printed circuit board coupled to said pair of terminal/support elements for support.

3. (canceled)

9. (canceled)

12. (canceled)

16. A method for reducing strain in a tire mounted assembly, comprising:

providing a substrate having a first surface and a second surface, wherein said substrate has length L and width W, wherein L>

2W, and W<

the length of arc subtended along the inner surface of a tire corresponding to 5°

of rotation measured from a line extending from the center of rotation to the inner surface of an unloaded tire inflated at rated pressure;

providing a pair of terminal/support elements extending from said first surface;

positioning said pair of terminal/support elements in a line 90°

±

10°

to a line in the direction of the length L; and

mounting the substrate in a tire so that the line 90°

±

10°

to the direction of the length L is aligned in the direction of rotation of said tire ±

20°

, whereby strain on the tire mounted assembly is effectively limited to one direction.

17. The method of claim 16, comprising;

positioning said pair of terminal/support elements in a line 90°

±

5°

to a line in the direction of the length L; and

mounting the substrate in a tire so that the line 90°

±

5°

to the direction of the length L is aligned substantially in the direction of rotation of said tire ±

10°

.

19. The method of claim 16, wherein mounting the substrate comprises securing the substrate laterally in the central portion of the tire summit.

20. The method of claim 16, further comprising positioning the pair of terminal/support elements less than about 18 mm apart.

21. The method of claim 16, further comprising providing the substrate with a width W of less than about 30 mm.

22. The method of claim 16, further comprising:

providing a piezoelectric device having a piezoelectric layer sandwiched between first and second conductive layers with one of said first and second conductive layers supported by said substrate layer,

whereby strain on the piezoelectric device is effectively limited to one direction.

23. The method of claim 16, further comprising:

providing a printed circuit board; and

securing said printed circuit board to said pair of terminal/support elements such that said printed circuit board is supported above said first surface,

whereby strain between said pair of terminal/support elements and said printed circuit board is minimized.

24. The method of claim 16, further comprising:

providing an elastomeric patch having a first surface and a second surface separated by a mesa having a height H;

securing said second surface of said substrate to said first surface of said elastomeric patch; and

securing said second surface of said elastomeric patch to an inner surface of a tire.

18. (canceled)